British Pat. No. 1,279,413, published June 28, 1972, discloses a process for making abrasive tools, such as grinding wheels, wherein diamond abrasive grits are uniformly dispersed throughout a porous metal matrix, which matrix is then impregnated with a liquid resin, either a thermosetting pre-polymer, or a molten thermoplastic. The liquid resin fills all accessible pores in the metal matrix and is then cured or cooled to a solid condition. Such construction is intended to retain the advantages of the strength and heat conductivity of a metal bond, with the controlled wear properties of a resin bond, particularly in the dry grinding of cemented carbide tools.
U.S. Pat. No. 2,258,774 to Kuzmick, discloses forming diamond wheels by mixing the abrasive with a low melting metal powder composition and a powdered pre-polymer of a thermosetting resin, and molding tools by the application of pressure and heat to the mixture contained in a mold of the desired shape. The metal is selected to have a melting point between 55.degree. C. and 327.degree. C., said to be equal to or lower than the temperature developed in the wheel during the grinding operations. As a result, the metal melts during grinding so as to provide a lubricating action.
Although related in structure to the composite matrices of the British patent and of Kuzmick, the composite material of this invention is intended for different grinding applications than either prior art reference and thus differs materially in its physical properties and composition. In particular, it is designed for the wet grinding of cemented carbide although it also gives improved results in dry grinding.
Sears U.S. Pat. No. 3,523,773 discloses a composite glass-resin bond.